HBR articles never cease to intrigue me. Here's something interesting and KMish. For your benefit, here's the gist - Research conducted by a HBR team indicates that boundaryless organizations exist only in theory and that silos are a given. Goes a long way to prove that the larger the organization the more difficult it will be to break silos.
Interestingly enough, just before reading this article I was wondering about why senior managers are so hesitant to aim for a consensus. They seem to run away from anything that calls for a consensus. They see it as time-consuming, pointless, unmanageable and so forth. There is this underlying urge to be quick and get things done rather than understand or admit the long term implications of not involving as many people as possible. No wonder we live in silos. Silos of departments, silos based on seniority etc. Communication, itself, is seen as a pain. Imagine discussing, debating and concluding on a regular basis! What we need to realize is that engagement of employees need not necessarily contribute to decision making but they are nevertheless required to ensure commitment and enthusiasm.
Web 2.0 will help in bringing to light the existing boundaries and provide a path for breaking them. Web 2.0 will enable movements within the organization that may or may not scale all the levels. More often than not, they may cut through the lower and middle levels but not enter into the senior levels of heirarchy. They may help erase some department-based boundaries but I am not so sure about seniority based boundaries. But the movement at the lower levels will, I believe, force the management to reconsider their management philosophies or face failure.